Film feeding presser



May 30, 1950 F. E. OAKHILL FILM FEEDING PRESSER W 2 w 0 D 6' d Patented May 7 30, 1950 UNITED STATES PATENT OFFICE mu mums rnsssnn Frederic a. 0.1mm, Wilmette, m, animuto Prismacolor, Inc., Chicago, 111., a corporation of Illinok Appliclttion November 10, 1945, Serial No. 627,820, I

which is a dlvlli on of applicationiserial No.

566,310, December 2, 1944. Divided and this application February-17, 1947, Serial No. 729,085

2 Claims, (cl. 211-23) This'invention relates to improvements in film feeding Dresser for photographic film printing machines, and other machines in which the film is advanced in a step by step manner, and the subject matter of the present application was divided out of my pending application, Serial No. 566,310, filed December 2, 1944, for an improvement in Film printing machines, and has been divided out of my pending divisional application Serial No. 627,820, filed November 10, 1945.

Upon the negative film are photographed groups of black and white images of an objective.

or many objectives. The individual images of each group are called frames since the images of each group are equally spaced apart by more or 1ess opaque bars and likewise the groups of frames are equally spaced apart by opaque bars.

In accordance with the present ihvention, the positive and negative films are advanced through a printing zone in a step by step manner by sprockets and are permitted to remain quiescent during the printing operation.

Referring now to said drawing which is merely illustrative of one embodiment of the invention, a frame structure is -provided upon which the several instrumentalities are mounted.

Mounted upon the front end of the frame structure is panel 8 upon which various instruments are mounted.

In Fig. 1 is shown a fragment of a positive film i2 and a fragment of the negative film 25. These films are trained around idlers 2|, 20 respectively and around driving-sprockets, two of which are shown at 22, 33.

r The film advancing sprockets are mounted respectively on shafts 22a, 33a. which are journaled in bosses I66, formed upon the panel 6, and said shafts are driven by gearing (not shown) which include spiral gear wheels I82, I which are mounted respectively on the shafts 22a, 33a. 7 A fragment of one of the driving spiral gear wheels is shown at it in Fig. 3.

The principal object of this invention is the a Associated withthe film driving sprockets are idlers 230 which positively hold the films in engagement with the sprockets. To facilitate Q threading the films between the sprockets and 25 idlers 23l|,the idlers for each sprocket are rota- The invention is clearly illustrated in the draw- 7 ing accompanying this specification, in which:

Fig. 1 is a front elevation of two film sprockets and associated film feeding pressers for holding the films in contact with the sprockets, one of the film pressers being shown in its retracted position;

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1, and

Fig. 3 is a view partly in side elevation of the mechanism seen in Fig. 1, and partly in vertical cross section taken on the line 3-3 of Fig. l.

Only such mechanism as relates to the present invention is illustrated .in the accompanying drawing, but the entire machine is shown and described in its entirety in the parent application, Serial No. 566,310 from which the instant application has been divided.

tively mounted upon a retractible slotted arm 23] which straddles the shaft 224 or 33a and is provided with a hub 232 in which is rotatably mounted a stud 233 which is provided with a knurled knob 234 and is rotatively mounted upon a pin 235 eccentrically disposed with respect to the axis of the stud 233 and secured to the panel 6 as by nuts. A threaded pin'23l is secured in the stud and has a reduced end which engages in a groove in the pin 235 and prevents accidental. disconnection between the arm HI and the pin 235. By rotating the knurled knob 234 upon. the eccentric pin to the position seen in the lower half of Fig. 1, the arm 23| and therewith the idlers 230 are retracted from the sprocket permitting the film to be readily trainedaround the sprocket.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention; hence, I do not wish to be understood as limiting myself to the exact form, construction, arrangement and combination of parts herein shown and described or uses mentioned.

What I claim as new and desire to secure by Letters Patent is:

1. In a film advancing mechanism, a film ad'- vancing sprocket, a driven shaft upon which said sprocket is mounted, a bearing member for said shaft, a retractable slotted arm straddling said shaft, said arm being formed with a hub, a pair of idiers rotatively mounted on said arm, for

retaining the film on the sprocket, a stationarily mounted pin formed with an annular groove, a stud eccentrically mounted on said pin and rotatably mounted in the hub of the arm and having a knob projecting beyond the arm, and a pin threaded in the stud and engaging in the groove of the first mentioned pin.

2. In a flhmadvancing mechanism, a. film advancing sprocket, a driven shaft upon which said sprocket is mounted, a bearing member for said shaft, a retractable, slotted arm straddling said shaft, said arm being formed with a hub, a pair of idlers rotatably mounted on said arm for retaining the film on the sprocket, a stationarily mounted pin, a stud eccentrically mounted on said pin and rotatably mounted in the hub of said arm and having a knob projecting beyond 1 4 the arm, and co-o'perating means on said pin and stud for maintaining the same in axial alignment.

FREDERIC E. OAKHILL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,857,116 Dina May 3, 1932 2,178,242 Runae Oct. 31, 1939 2,369,089 Thomas Feb. 6, i945 FOREIGN PATENTS Number Country Date 437,805 Germany Dec. 2, 1926 

